OOP in Python, specially Composition

So, I've been trying to get my hands-on experience on Python and this OOP concept just started coming along. I can't seem to understand the concept of Composition clearly with good examples like a car example. Any help on this would be great!

I'll provide a code which uses Composition, Can anyone explain the use of Composition here?

class Clothing:
    stock={ 'name': [],'material' :[], 'amount':[]}
  def __init__(self, name):
      material = ""
      self.name = name

  def add_item(self, name, material, amount):
      Clothing.stock['name'].append(self.name)
      Clothing.stock['material'].append(self.material)
      Clothing.stock['amount'].append(amount)

  def Stock_by_Material(self, material):
      count=0
      n=0
      for item in Clothing.stock['material']:
          if item == material:
              count += Clothing.stock['amount'][n]
              n+=1
      return count

  class shirt(Clothing):
      material="Cotton"

  class pants(Clothing):
      material="Cotton"

  polo = shirt("Polo")
  sweatpants = pants("Sweatpants")

  polo.add_item(polo.name, polo.material, 4)
  sweatpants.add_item(sweatpants.name, sweatpants.material, 6)

  current_stock = polo.Stock_by_Material("Cotton")
  print(current_stock)